--- old/src/share/vm/gc/g1/g1StringDedup.hpp	2017-02-23 11:24:33.622339727 +0100
+++ new/src/share/vm/gc/g1/g1StringDedup.hpp	2017-02-23 11:24:33.494334717 +0100
@@ -90,6 +90,7 @@
 class ThreadClosure;
 class outputStream;
 class G1StringDedupTable;
+class G1StringDedupUnlinkOrOopsDoClosure;
 class G1GCPhaseTimes;
 
 //
@@ -130,6 +131,7 @@
 
   static void oops_do(OopClosure* keep_alive);
   static void unlink(BoolObjectClosure* is_alive);
+  static void parallel_unlink(G1StringDedupUnlinkOrOopsDoClosure* unlink, uint worker_id);
   static void unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive,
                                 bool allow_resize_and_rehash, G1GCPhaseTimes* phase_times = NULL);